Janus Henderson Mid Cap Value Fund Expense Example - Class D Shares [Member] - Janus Henderson Mid Cap Value Fund - Class D	Jun. 30, 2026 USD ($)
Prospectus [Line Items]
Expense Example, with Redemption, 1 Year	$ 69
Expense Example, with Redemption, 3 Years	218
Expense Example, with Redemption, 5 Years	379
Expense Example, with Redemption, 10 Years	$ 847

Reference 1: http://www.xbrl.org/2003/role/presentationRef
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